Machine for polishing stones



(No Model.) v 2 Sheets-Sheet (1.

M. HURTH.

MAGHINE FOR POLISHING STONES- Patented Jan.

o 1 llailll r INVENTEIR 0. 96M

gawk/$ (No Model.) 2 Shets-Sheefi 2.

M. HURTH. MACHINE FOR POLISHING STONES. No. 396,162. Patented Jan. 15,1889.

WITNESSES mvemua s Photolflhngrapmr, Wauhinglon. a v.

PATENT MICHAEL HURTI-I, OF POUGHKEEPSIE, NEIV YORK.

MACHINE FOR PQLISHING STONES.

SPECIFICATION forming part of Letters Patent No. 396,162, dated January15, 1889.

Application filed April 13, 1888. Serial No. 270,551. (No model.)

To all whom it may concern.-

Be it known that I, MICHAEL HURTH, of Poughkeepsie, Dutchess county,State of New York, have invented a new and Improved Machine forPolishing Stones, of which the following is a specification.

This invention relates to amachine for polishing slabs of marble,granite, or other stones. The machine is so constructed that thepolishing-tool is automatically fed across the entire surface of thestone and is at the same time revolved during the polishing operation.

The invention consists in the various features of construction, morefully pointed out in the claims.

In the accompanying drawings, Figure 1 is a sectional side elevation ofmy improved machine. Fig. 2 a horizontal section on the line a: in,Fig. 1. Fig. 3 is a vertical longitudinal section of the machine throughthe center of crosshead b.

The letters a a represent the uprights of the frame of the machinejoined on top bya crosspiece, a. The uprights a are grooved for thereception and guidance of a verticallymovable cross-head, b, suspendedfrom the cross-piece a by means of the adj ustingscrew 0, by which thecross-head may be raised or lowered. (Zouliter-weights (Z, for relievingthe screw c, are suspended by chains (1, that pass over pulleys d andare attached to the cross-head.

Through the cross-head 1) there pass two shafts, c, that project beneaththe cross-head. One of these shafts should also project above thecross-head, to carry a fast pulley, 6, connected by belt 6 to fastpulley e on operating-crank e. The drawings show both shafts c toproject above the cross-head and both provided with. a fast pulley. Thisenables the machine to be worked from either the right or'the left handside. The lower exposed ends of shafts e carry rollers f, fast on theshafts, such rollers being surrounded by an endless belt or apron, g.Above the rollers there is placed a fixed oblong endless rack, 71, and afixed oblong flange, i, as shown.

At their lower extremities the shafts e are journaled in a plate, 7,having a flange, In, similar to flange L. The rack h and flange L aresecured to cross-head Z) by bolts Z I, while the plate j and flange aresecured to the rack h by bolt Z, as shown in Fig. 3.

To the apron g there is secured, in suitable manner by straps orotherwise, a tube, m,-

through which passes a shaft, 01, the lower squared end of which isreceived by a socket, 0', of the polishing-tool o of suitableconstruction. This tool rests by gravity upon the slab A to be polished.The upper end of shaft 11 carries a gear-wheel, p, meshing in endlessrack h. The tube at is surrounded by a pair of collars, q, having twopins or guides, 0, one at each side of the flanges i k. The pins orguides 7 project against the inner surfaces of the flanges i k, asshown, and their function is to hold the gear-wheelp in contact withrack h, even should the belt g become somewhat expanded by wear.

The operation of the device is as follows: By turning crank e therollers f will be revolved to impart motion to the belt g. This beltwill carry the tube m with it, and thus the tube will be made to travelin an oblong path, carrying the shaft 01 and tool 0 with it. At the sametime the shaft a will be revolved by gear-wheel p, and thus the tool 0will be revolved simultaneously while being carried over the slab. If alarger slab is to be polished, rollers f must be introduced, that arewider apart. For this purpose the cross-head Z) is perforated, as at bBy withdrawing bolts Z Z the rollers f are removed and rollers widerapart may be put in place, the shafts of whichpass through theperforations U The object of making the cross-head b verticallyadjustable is to permit the introduction of stones of differentthicknesses.

What I claim is 1. The combination of a frame with a pair of rollers, asurrounding apron, a rack, a tube secured to said apron, a shaft passingthrough said tube and carrying a gear-wheel meshing into the rack, and apolishing-tool secured to the shaft, substantially as specified.

2. The combination of a frame with a pair of rollers, a surroundingapron, a rack, a pair of flanges, a tube secured to the apron andprovided with a pair of guide-pins operating in conjunction with theflanges, and a toolcarrying shaft passing through the tube and in gearwith the rack, snhslzmlinl tied.

.J. The combination of a frame with a vorl y as spooiand in gear withtho raolglzhe shaft carrying the polishing-tool, substantially asspecified.

'1 Y )r\ ideally-adjnstable cross-head, a pair of rollers MTUIAEL 1suspended l herofrom, nn apron surrounding \Vitnossos: said rollers, arank, a lube mun-0d to said 1 V. l-ijnmsl ln, apron, and a shaft passingthrough said tube i HENRY E. OEDER

